DTC P1215: Ground Fault Detection Indicated: Description

WARNING: This page is about a different car, the 2002 GMC Savana Special, 2002 GMC Savana Camper Special, 2002 GMC Savana, and 2002 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.

The Alternative Fuels Engine Control Module (AF ECM) contains electronic devices called output driver modules. The output driver modules provide switchable outputs, control circuits, for operating solenoids, relays, telltales and other devices. Each of the outputs has an internal fault line that the AF ECM can monitor for faulted circuit conditions.

Two types of outputs can be utilized. High side drivers supply voltage on the control circuit. Low side drivers supply a ground on the control circuit. In order for the fault line to detect a failure the state of the control circuit must be opposite of the expected state. If the AF ECM is commanding an output ON, then 0 volts should be monitored by the fault line. If the AF ECM is commanding an output OFF then the voltage supplied to the controlled device should be monitored by the fault line.

This DTC is used to indicate that the AF ECM fault line has monitored a control circuit fault.

This DTC monitors the following low side driver circuits:

The Fuel Control Solenoid (FCS) control circuit.
The Idle Control Solenoid (ICS) control circuit.
The Alternative Fuels Operation (AFO) signal control circuit.
The Low Pressure Lock-Off (LPL) solenoid control circuit.
The EVAP canister purge enable control circuit.